


The Science of Falling in Love

by DonnesCafe



Category: Sherlock (TV)
Genre: Falling In Love, First Kiss, First Time, Fluff, Love, M/M, Romance, Sherlock is a bit slow but he gets there
Language: English
Status: Completed
Published: 2015-11-17
Updated: 2015-11-17
Packaged: 2018-05-02 03:23:55
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,112
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5232077
Author URL: https://archiveofourown.org/users/DonnesCafe/pseuds/DonnesCafe
Summary: <blockquote class="userstuff">
              <p>Love and brain chemistry. John and Sherlock.</p>
            </blockquote>





	The Science of Falling in Love

**Author's Note:**

> Quotes are from a post I saw on tumblr about the science of falling in love.

_1\. “The hypothalamus releases dopamine – ecstasy and excitement…”_

He was not his transport. He was his mind. To the extent necessary to serve his mind, he grudgingly intervened to manage the transport. He begrudged any time and attention given to his body, but it required regulation. Some experiments had been more successful than others. Drugs had proved to be the most effective intervention to achieve the crystal clarity of thought he craved, to regulate the highs and lows, to slow his racing thoughts, to ease the crushing boredom of life. Unfortunately… cruelly… his assumption that he could control his use had proved unfounded. His protestations to his brother that he wasn’t an addict ended after the second overdose. He had been clean since then, but he still missed the drugs. 

Leaning against the wall, laughing with a man who had just killed someone for him, he felt the welcome lift and surge of excitement at a case well-concluded. He looked over at John Watson. Such a bland person to be so dangerous, so cool under fire. Something else fired in his brain. Dopamine. Interesting. 

_2\. “As dopamine levels increase, serotonin levels decrease. Lower levels of serotonin are similar to levels of people with obsessive compulsive disorders. This may result in feelings of obsession or infatuation…”_

He felt uneasy. Not bored. He had spent a contemplative morning working on Cage’s _Freeman Etudes_. John objected to Cage’s dissonances. John’s taste in music was appalling, but Sherlock tried to accommodate him. John admired his violin playing but preferred the baroque and the romantic, so Sherlock practiced Cage and Rosza when he was out. John had gone to Tesco earlier. 

Earlier. Much earlier. Sherlock lowered the bow. He was uneasy because John had been gone too long. Likely nothing. A walk in the park. A stop at a café. Since the pool, he suddenly realized, he was subconsciously tracking John’s movements. He was… concerned. He reviewed the last two weeks. John in Baker Street. John not in Baker Street. Oh. When John was here, Sherlock noted an increase in dopamine levels. He had gotten used to monitoring his brain chemistry. He recognized dopamine’s effects. When John wasn’t in Baker Street, he felt a distinct lack of… something. Interesting. 

_3\. “The body produces nerve growth factor. NGF higher in people newly in love. Intensity of romantic feelings…”_

Miscalculation. He had miscalculated. John dragged his chair back and stood. Emotions passed over his face too quickly for Sherlock to read. He had never been good at this. But he thought he saw… he thought before the anger there was love. Love. He had to say something. 

He tried to apologize. To explain. This wasn’t working. Anger, bitterness. Perhaps it was the moustache. John’s fist crashed down on the table. 

John’s face was different. Facial hair. More lines. Something shuttered in it. The facial hair was ludicrous. Perhaps he had misread what he thought he saw. He wasn't good with emotions. 

Suddenly John’s hands were on him. Perhaps he shouldn’t have said anything about the facial hair. Oh. John’s hands were on him. They were falling. John. Euphoria. What was this? His brain ran like lightning as they fell. Hypothalamic-pituitary-adrenal axis. He wanted John’s hands on him forever. His heart was pounding. He felt the itch of cortisol run through his veins. Tropomyosine receptors. Good God. How could he have been so blind? He was in love with John Watson. His head hit the floor and he felt John’s body, warm and solid on top of his. He was stunned. In more ways than one. 

_4\. “Oxytocin and vasopressin are responsible for feelings of connection and commitment….”_

Sherlock sank down onto the sofa without even taking off his coat. An afternoon strategizing with Mycroft had only distracted him temporarily from the emotions washing through him. Sentiment. Inconvenient. Undeniable. Moriarty was, perhaps, undead. Sherlock himself was, perhaps, temporarily reprieved from a death sentence in Eastern Europe. Yet all he could think about was standing across from John on the tarmac. The thought that he was never to see John again had nearly undone him. The thought that he would never be able to tell John he loved him. Sherlock sighed. What did it matter, though, after all? What difference would it ever have made? 

Suddenly the door slammed open. John crossed the room in long angry strides. 

“John….” He struggled up. He didn’t want John to see tears on his face. He turned away. 

Strong hands turned him. One cupped his chin, the other threaded through his hair. John was kneeling beside him. 

“I thought I had lost you. Again. My god, Sherlock….” 

Hours later, in his bed, he had time to analyze and survey his brain chemistry. Oxytocin. Vasopressin. Orgasm. Orgasms, he corrected. He felt… splendid. He turned in the circle of John’s arms. 

“John, I…,” he hesitated. What about Mary? What about the baby? 

John’s arms tightened. His eyes remained closed. 

“Shh. G’back to sleep. Don’t worry about what I know you’re worrying about. We’ll work it out. I love you, too. I’m not leaving. For anything. Ever again. Go back to sleep.” 

_5\. “…activates activity in the amygdala , moderates stress and fear, and unites people in love.”_

He felt like utter shite. Dry mouth, pain everywhere. 

“Jhn..J…” 

He felt a hand on his forehead. Then the soft brush of familiar lips pressed onto the back of one hand. 

“Shh. Don’t try to talk. You’re in hospital, but you’re going to be ok. Thank God. But if you ever do that to me again, I swear I will kill you myself.” 

Sherlock opened his eyes. Closed them again. The light was painful. 

“Are you in pain?” 

He grunted. Of course he was in pain. Pearson and a confederate had beaten him within an inch of his life. 

“Of course you’re in pain,” John said, echoing his thoughts. “And you bloody well deserve it. Why the _hell_ are we always having this same conversation, Sherlock? Hmmm? Why did you go without me? Why do you think you don't need me?" 

“Always need you,” he mumbled. Good God, his voice sounded weak. “Hurts….” It did. His ribs hurt. His head hurt. It hurt that he had worried John. Again. 

“Sorry. M’sorry.” 

“I know. I love you, you stupid, stupid git. Here, I’ll up your morphine.” 

Sherlock tried to smile. Morphine was good, but oxytocin was better. 

“Get … bed with me, John.” 

“Don’t be ridiculous. You’re hooked up to too many monitors.” 

Silence. 

“Well, maybe I could unhook a few things on this side. Just for a minute.” 

Mycroft had been so wrong, Sherlock thought. Love was a wonderful thing.


End file.
